Bill calculated averages from all the data which I thought was a really interesting; I included averages from the 04-05 season to the present.

I added lines from both Stonehill stations to Bill's station. According to Google Maps, Bill is at 1640' and is approximately 1.25 miles WNW of here.

That puts him at the exact same elevation as PacRad, but he's on slightly flatter terrain (no canyon walls directly adjacent to him). I speculate that the shape of the terrain more than the elevation is causing Dan to average almost 2" more than Bill and me about 3/4" more than Bill.